Kiln for drying lumber.



No. 829,497. PATENTED AUG. 28, 1906. 0. WILLIAMS.

. KILN FOR DRYING LUMBER.

APPLICATION FILED APRJS, 1906.

3 SHEETS-SHEET 1.

m WITNESSES; H INVENTOR No. 829,497. PATENTED AUG. 28, 1906,

. 0. P. WILLIAMS.

KILN FOR DRYING LUMBER.

APPLIOATION FILED APR. 16, 1906.

3 SHEETS-SHEET 2 u\ 3 WITNESSES: INVENTOR, (,6. c, Wfl Q QTM PATENTED AUG. 28, 1906. G. F. WILLIAMS.

KILN FOR DRYING LUMBER.

APPLICATION FILED APR. 16, 1906.

s SHEETS-SHEET a.

INVENTOR WITLIESSES; C. Wi

UNITED sTATEs PATENT OFFICE.

CHARLES F. WILLIAMS, or OOLDWATER, MICHIGAN.

KILN FOR DRYING LUMBER.

Specification of Letters Patent.

Application filed. April 16, 1906. Serial No. 811.883.

Patented Aug. 28. 1906.

tains tomake and use the same, reference being had to the accompanying drawings, and

to the characters of reference marked thereon,

which form a part of this specification.

My invention relates to kilns for drying lumber, staves, headings, or the like; and it has for its object to improve upon the construction of kiln shown. and described in my former Letters Patent, No. 772,767 granted October 18, .1904, whereby a more eflicient and economical kiln is provided.

The primary feature of improvement in my present construction consists in the provision of" simplified means for utilizing and causing the moist air which would otherwise be expelled to the atmos here from the kiln to be returned thereto. a jacent its entrance or wet end. The return ,of this moist air to the wet end of the kiln-building material aids in the sweating process and it is found revents the checkin and hollow-homing, w 'ch occurs in certain ln'nds of lumber when subjected to a dry-air. treatment during the sweating thereof.v

Further improved features of; my resent construction of kiln will be apparent y reference to the following description and to the L accompanying drawings, in which Figure 1 is'a horizontal section of-th'e wet end of my improved kiln, showing a plan of the tracks, piping, and air-conduits. Fig-52 e is a vertical section thereof, taken "on the m a: in Fig; 1. Fig. 3 is a sectional plan view of the dry end of thekiln, similar to and formrepresents the ing a' continuation of Fig. 1. Fig. 4 is a broken vertical section taken on the line a: :v

in Fig. 3. Fig. 5 isa cross-section of the kiln, taken on the line m m in Fig. 1; and Figs. 6 and 7 are slight'modifications of the central transverse airduct of the kiln, Fig. 6 being a top plan view and Fi 7 a side elevation thereof with" portions roken away and the latter'showing the exhaust-fan hous-' mgs in section.

Referring to gigs. 1 to 5 of the drawings, 1

-' n-building, which may be" i of any desired length or Width and of anyv suitable construction to render it air-tight. Door-openings 2 are provided at each end of the kiln for the admission and discharge of trucks upon which the lumber or stock to be dried is piled, and these openings are closed by doors. (Not shown.) The rails 3, on which the .trucks move, are supported by sills or track-timbers 4 some distance above the floor, ground, or plane of the lower edge of the building.

Extending crosswise of the kiln adjacent each end thereof and a short distance below the plane-of the track-timbers 4 is an air duct or chamber 5, which is closed to the interior of the kiln except for a narrow air-exit slit or opening 6, disposed, adjacent the inner up er edge thereof .and extending across the bulldin as shown in Figs. 1, 2, 3, and 4. The ends 0 these airgducts open without the kiln and are rovided with doors or dampers The air admitted to the ends of the kiln is expelled therefrom through a transverse airduct 8, disposed centrally of the building and having one end communicatin with an exhaust-fan 9, which is desi 'ne to create a forced draft in the duct to draw the air from v the kiln-room. This central air-duct is purpose hereinafter explained, I provide a transverse duct 11 ad'acent the door at the 7 for controllmg the admission of air thereto.

wet or entrance end 0 the building and con- "-nect one endof this with the exhaust of the -1 fan 9 through the medium-of the conduit 13 I F which is disposed at the side ofthe building.

. The air which is driven through the-conduit 13"and into the duct 11 is ell-gelled there- 'from to the inte ior of the buil g through the slit or opening 14 in the top of sa1d duct; Theconduit 13 is provided at its outer end direct all of the returned air into the kiln, or may be adjusted to expel all or only a portion of the air to the outer atmosphere, asthe operation of the kiln may require.

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with a door or damper 15, whichmay be-po- 1 sitioned to entirely close its opemng, so as to In order to heat the air'which enters the kiln through the ducts or, chambers 5, "a s'e- IIO ries of pipes, adapted to be heated by live or exhaust stearn,'are arranged at each endof the building immediately below the plane of the rails 3 and above the chambers5, as

, through the i'eTed-pr e 21.

shown in the drawings. A convenient construction of heaters consists of connected headers16 and 17, arranged at the ends'of the building, the connections between these headers forming the heating-surfaces. These connections preferably consist of a lurality of lines or sections of pipe 18, which are arranged in parallelism and connected at their endsdirectly to the headers by nipples, ties, elbows unions &c., as shown, or in any other suitable-manner. By this construction the water of condensation instead of fiowin from one pipe 18 to another, as described an shown in my said former Letters Patent, will flowfrom each section 18 directly to the header 17, which connects, through outlet pipes 19 with steam-traps 20 of any suitable construction. Steam is supplied to the two heaters The heater at'the wet or entrance en of the is plreferably made longer than the'heater at t e dr or exit-end and is shown as-comprisingptwo s of connecting-pipes 18, while the ot er heater has three lines of such pipes. To facilitatethe removal of the pipes L8 for'the purpose of cleaning, repair, or'substitution, each is made in two 'SBGUODS, which are coupled together by unions 22}.

In operating the kiln the trucks I the lumber or stock to be dried are. move successively step by steilfnhroughthe When first placedin the ,the stock is directl over the heater in the entrance end of the ln, but between the door and the air ductor chamber 5 at such end, said duct or- .chamber bein positioned a proximately,

two-thirds of t eway forward om the rear end of the heater, as: shown, thus causing the v v and provided intermediate such ends with an stock to besub'ected to a sweating process. which is aidedby the stagnancy of the heated air at such end; Aiter the stockhas been sufliciently sweated is moved forward to 7, permit the dry hot air arisingfrom the duct or chamber 5 to pass therethrough and. ope}:-

ate to take the moisture therefrom.-

forced draft created b causes the moisture-la on .air after .passin up through the stock .to take a downwar course and find an exit from the kiln through in the duct 11.

'ing the sweating process materiall conduit or be returned to the wet or entranceend of the kiln through'the-slit or opening 14 This returning of the moist air toand discharging 1t through. the stool; duracilitates such operation and prevents t e stock from cracking or becoming hollow-horned,

which OOILditlOll ver fre uently occurs with certain kinds of lum er w en sweating'1s oc-. easroned bya dry hot air. After GIQSSIDg the 'to prevent a commingling-of the .dry and Z'nected motors or engines 9,

2. Akilnprovidedwith the exhaust-fan '9;

' end oi the kiln whereby to return the expelled f air thereto, means forereat" air-exit and means-for heating the air admitted to the kiln, I -atmostween the air-exit'and the 'wet end of the-kiln central air-duct 8 the stock is subjected to the drying effect of the air which enters through the duct or' chamber 5 at the dry or exit end of the kiln and is heated by the heating system at that end. This air is also drawn into the central duct 8-through the contiguous slit or'opening 10 therein, due to the action of the an 9, and eommingles therein with the moist air entering from the wetend of the kiln; The combined areas of the two slits or X openings 10 in the central 'duct 8 are approxienables it to discharge the dry and the moist sthereoh In these fig.-. ures a represents the central air-duct, which isprovidedeachside with the intakeslit air from opposite en or openin'zgh; c, the exhaust-fan which creates.

the draft in the. wetend of-t'he ln'ln and returns the .moist" air thereto, (1, an exhaustfan which isdis sed at the opposite end of the duct to the an -.c and. has its exhaust directed into a stack e, throughwhich the dry' air'is expelled to the atmosphere. Inorder moist air within the ductand cause each to be directed. to the proper fan, a diagonally- ,disposed vertical partition f is positioned. therein, which-divides it into two trian .ular' chambers, asshown. The fans 0 and are shown as being perated by directlycon-' Ha thus described my rnventiong' what.

Lciaim as new, and-desire to Seal-web? ters Patent, is I 1 l 1.. A having a wet end. and a end,

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air-exit whichactsas a division. therefor, and a conduit leading from said exit to and com end air-inlet-chamdraft therein. 1

here and intermediate air-exit, a conduit leadingfrom: theair-exitmeansto the wet a dratt in said 3. 'A kiln provided with and inlet.- ducts and; intermediate air-exit, connectionbe whereby to return theexpel-fed fair thereto,

means for creatinga .draftin the air-exit,

means for controlling the return of air'to the kiln, and means located in the ends of the:

kiln for heating the air. a v

4. A kiln provided with end air-inlet ductsand an intermediate air-exit duct the inletopenings towhieh latter are located in the tially the width of the building, in combinaend of the kiln-building, means for drawingthe air fromthe kiln-room through said exit and returning it to the room at the end thereof, means for admitting air to the building, and means for heating the admitted air.

6. In a kiln, a heating system disposed at the entrance or wet end thereof and extending a distance therein, and an air-inlet duct disposed under the heating system and transversely of the building and positioned a considerable distance in advance of the entrance to the kiln-room whereby to form a dead-air space at such end.

7. In a kiln, a plurality of steam-pipes arranged longitudinally thereof at its entrance end to form a heater, an air-inlet duct disposed under the plane of the heater transversely of the building and having a narrow dischar e slit or opening extending substantially 17% being disposed adjacent the rear end of the heater whereby to form a dead-air space at the entrance end of the roomfand air-exit means.

' 8. A kiln provided withend ducts for the inlet of air and intermediate air-exit means, said end ducts extending transversely of the kiln-room and having damper-controlled inlets and' elongated slits\or openings for the discharge of air to the room, in combination With means located at the ends of the kiln for heating the air.

In testimony whereof I have hereunto signed my name to this specification in the presence of two subscribing witnesses.

CHARLES F. WILLIAMS.

Witnesses:

CHARLES N. LEGG, GHAs. F. HOWE.

e Width ofthe kiln-room, said duct 

